The invention relates to a proxy. When establishing a connection from a subscriber terminal to a server of a content provider, a proxy participates in establishing the connection and/or billing for it.
In a normal situation, a subscriber terminal connects to an access network and a server of a content provider is connected to a service network. The access network can be a cellular radio access network, such as GPRS (General Packet Radio Service) or WLAN (wireless local area network). The service network is typically an IP (Internet Protocol) network, such as the Internet or closed subnetworks thereof (intranet, extranet, etc.). These network types are naturally only illustrative and not restricting examples.
To provide a concrete example, the invention will be described using a GPRS network. GPRS is a packet-switched telecommunications network operating on top of the GSM network and can be used to switch Internet telecommunication to terminals. The terminals can be mobile phones, hand-held computers and portable computers, for instance.
The connection from the GPRS network to the Internet is through a gateway GPRS support node GGSN. The GPRS network establishes a tunnel from the edge of the network to the terminal. In other words, the network processes IP packets of users in the terminal and GGSN only. In a normal situation, one terminal uses only one GGSN node at a time, but if the terminal is in between switched off, for instance, it can use another GGSN node next time. However, all traffic between the terminal and an external network (such as the Internet) only goes through one GGSN node at a time.
The Internet interface in connection with a GGSN node is called a gateway and different technical services can be provided through it. Typical services include an IP address translation service NAT (Network Address Translation) that in practice provides a limitless number of addresses in a GPRS network, a WWW traffic proxy, a cache memory, and firewall services. The services can be technically implemented in different parts of the network or in different equipment.
Billing in the GPRS network differs from billing in a conventional mobile network in that it provides more alternatives. A teleoperator may bill for the use of the network on the basis of one or more of the following: 1) a fixed monthly charge; 2) the time the terminal is connected to the GPRS network (even though it does not necessarily communicate anything); and 3) the amount of data transmitted in the network (bytes or packets, for instance).
A general problem underlying the invention is that the access network side (a public switched telephone network or cellular mobile network, for instance) has mechanisms for billing the subscriber of the terminal on the basis of the number that is called or to which a short message is sent. The billing methods of access networks do not, however, allow billing on the basis of content in such a manner, for instance, that the charge for retrieving the WWW pages of a content provider would depend on the price set by the content provider on the information. The present billing systems of the GPRS network do not take into account the content of the telecommunication, only the connection time and the traffic volume.
This basic problem is generally known in the field and solutions for it are actively discussed in the trade forums. The problem is called ‘billing for content’.
A number of sub-problems can be derived from this basic problem:    1 How can a user monitor his or her own expenses when a solely volume-based or content-based billing is used?    2 How to implement a 0800-type toll-free service, i.e. the service is billed to the content provider (not the user)?    3 How can the payer of the access network (e.g. GPRS) connection who is not necessarily the same person as the user, restrict the use of the service?    4 How can a person who has bought a license to use a chargeable data content gain access to the content after a technical failure or for a fixed time so that the license to the service entity is paid once (like one buys an entire newspaper)?    5 How will the time of day be taken into account if the service charge depends on it?    6 How to direct the costs to the correct user?
Present GPRS network solutions for pricing content are based on the fact that the content (generally WWW pages) to be provided to the customer are located in a content server managed by the teleoperator (i.e. the operator of the access network) and the server is connected to the billing system of the teleoperator. The use of the content can be restricted using a user identifier and password combination. Alternatively, there may be a telecommunications connection for transmitting billing data between the billing system of the teleoperator and the service platform of the content provider. In these solutions, all traffic is priced using one pricing model. Billing techniques used on the Internet are not very advanced, either. Most systems allowing billing for content are based on a separate user agreement (the existence of which is verified by a user identifier and password). The payment is done by a data network-independent technique, such as credit card or bank transfer.
A specific problem with the known arrangements described above is that they do not offer simple payment transfers between the operators of the access network (such as telephone network or mobile network) and service network (such as the Internet), because the operator of the service network is not in practice able to bill the subscribers of the access network. The problem is slightly simpler if the same operator manages both the access network and the service network, but in this case, too, the operator cannot implement a flexible arrangement for content-based billing, and this requires that the content service is implemented in a certain access network only and is thus not available to subscribers of other access networks. Thus, an Internet site administrator, for instance, has not been greatly motivated to adapt corresponding services to suit mobile network terminals. A second problem caused by this is that only a small number of services has been provided to mobile subscribers.